1. Field of the Invention
The present invention relates generally to the removal of pollutants and cleanup of storm water and wastewater. More particularly, the present invention relates to materials for removing toxic metals from storm water runoff and wastewater.
2. Description of the Prior Art
The military including the Department of Navy are under increasing pressure from regulators and local communities to substantially reduce the amount of pollutants being discharged with storm water into harbors, bays, lakes, and streams. The military needs to remove toxic contaminants from runoff water, to avoid Notices of Violation of environmental statutes and regulations by Federal, state and local regulatory agencies to avoid costly fines and improve the public perception of military's environmental stewardship.
Military installations must now comply with National Pollutant Discharge Elimination System (NPDES) storm water permit requirements. Compliance needs to achieved by completing a multi-phase process. An important step in this process is implementation of non-structural (or pollution prevention) best management practices (BMP) to reduce the amount of pollutants that enter storm water runoff. Non-structural BMPs are usually simple changes in management practices that reduce the potential contamination of storm water runoff. Examples of non-structural BMPs include activities such as regularly sweeping work areas, training employees to properly dispose of wastes, cleaning catch basins, and storing materials under covered areas.
However, implementation of best management practices pollution prevention alone may not be adequate to comply with discharge regulations requirements. If all applicable management practices have been implemented and contaminants in the storm water runoff from the site still exceed the permitted discharge limits, then treatment of the storm water runoff is required. Treatment of storm water runoff to reduce runoff volume or pollutant concentration is termed structural best management practice.
Storm water runoff from military industrial operations can be roughly characterized has having elevated metal content, moderate suspended solids and organic content, and low nutrient and bacterial content. The elevated metal content in storm water runoff from Navy industrial sites can be attributed to outdoor metal working processes such as cutting and grinding, storage of metal objects outdoors, and use of metal bearing materials such as corrosion inhibiting and anti-fouling paints.
Storm water runoff from military industrial sites is not easily treated by current commercial off-the-shelf technology. Most of the current technology is designed for municipal applications such as trash, nutrient, and sediment removal. Also, most storm water treatment technology requires large areas of land for infiltration basins and similar structures. Space is often at a premium at many military sites, especially waterfront locations.
The main chemicals of concern for example at a military port or harbor are copper, mercury, zinc, total chlordane, total PCBs, and PAHs (poly-aromatic hydrocarbons). Contaminated sediments at a harbor or port facility pose a substantial threat to aquatic life, wildlife, fisheries, and human health. Fish and bottom-dwelling creatures suffer disease, death, reproductive failure, or impaired growth upon exposure to pollutants in the sediment. Trace metals (i.e., copper, mercury, zinc) in the sediments are harmful particularly because they persist in the marine environment and bio-accumulate up the food chain, traveling from marine organisms to fish then to humans.
The U.S. Environmental Protection Agency issued Federal regulations for storm water discharges (40 CFR Parts 122, 123, and 124). These regulations require specific categories of facilities that discharge storm water associated with industrial activity to obtain a National Pollution Discharge Elimination System permit. In addition, facilities are required to implement Best Available Technology Economically Achievable and Best Conventional Pollutant Control Technology to reduce or eliminate industrial storm water pollution. The EPA developed a four-tier permit issuance strategy for storm water discharges associated with industrial activities. These are:
Tier I, Baseline Permitting—One or more general permits will be developed to initially cover the majority of storm water discharges associated with industrial activity.
Tier II, Watershed Permitting—Facilities within watersheds shown to be adversely impacted by storm water discharges associated with industrial activity will be targeted for individual or watershed-specific general permits.
Tier III, Industry-Specific Permitting—Specific industry categories will be targeted for individual or industry-specific general permits.
Tier IV, Facility-Specific Permitting—A variety of factors will be used to target specific facilities for individual permits.
The EPA regulations allow States to issue General Permits or individual permits to regulate storm water discharges. The General Permit generally requires dischargers to:                A. Eliminate unauthorized non-storm water discharges;        B. Develop and implement a storm water pollution prevention plan; and        C. Perform monitoring of storm water discharges and authorized non-storm water discharges.        
Activities that take place at industrial facilities, such as material handling and storage, are often exposed to storm water. The runoff from these activities discharges industrial pollutants into nearby storm sewer systems and water bodies which may adversely impact water quality.
To limit pollutants in storm water discharges from military industrial facilities, a National Pollution Discharge Elimination System (NPDES) Phase I Storm Water Program includes an industrial storm water-permitting component. Operators of industrial facilities included in one of the 11 categories of storm water discharges associated with industrial activity set forth at 40 CFR 122.26 (b) (14) (I)-(xi) that discharge storm water to a municipal separate storm sewer system or directly to waters of the United States require authorization under a NPDES industrial storm water permit. If an industrial facility has a Standard Industrial Classification code or meets the narrative description listed in the 11 categories, the facility operator must determine if the facility is eligible for coverage under a general or an individual NPDES industrial storm water permit. Of the 11 categories of storm water discharges associated with industrial activity, those applicable to the Navy are described below:
Category 1: Facilities Subject To Storm Water Effluent Limitations Guidelines, New Source Performance Standards, Or Toxic Pollutant Effluent Standards.
Category 4: Hazardous Waste Treatment, Storage, or Disposal Facilities.
Category 5: Landfills, Land Application Sites, And Open Dumps Receiving Industrial Wastes.
Category 6: Recycling Facilities.
Category 8: Transportation Facilities.
Category 9: Sewage or Wastewater Treatment Works.
Category 10: Construction Activities Including Cleaning, Grading, and Excavation of Areas Over Five Acres.
Category 11: Light Industry Where Industrial Materials, Equipment, or Activities are Exposed to Storm Water.
The US EPA report Overview of the Storm Water Program (EPA document EPA 833-R-96-008) documents the environmental requirements under Federal regulations for removal of pollutants from storm water runoff.
Many military installations will also be affected by the proposed EPA total maximum daily load (TMDL) rule. TMDL is the amount of a pollutant that a stream, lake, estuary or other water body can accept without violating state water quality standards. Once a TMDL is established, responsibility for reducing pollution is assigned. Thus, military installation's point and non-point sources may be subject to discharge limitations set by TMDLs. TMDL based regulations are slowly being developed and affect few military activities at this time. State or local regulations may be more stringent than Federal regulations.